There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem():

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
 nft_add_set_elem+0x14b0/0x2990
  nf_tables_newsetelem+0x528/0xb30

Furthermore, there is a possible use-after-free while iterating,
'node' can be free'd so we need to cache the next value to use.

Fixes: c9e6978e2725 ("netfilter: nft_set_rbtree: Switch to node list walk for overlap detection")
Signed-off-by: Florian Westphal <fw@strlen.de>

nft_trans_FOO objects all share a common nft_trans base structure, but
trailing fields depend on the real object size. Access is only safe after
trans->msg_type check.

Check for rule type first.  Found by code inspection.

Fixes: 1a94e38d254b ("netfilter: nf_tables: add NFTA_RULE_ID attribute")
Signed-off-by: Florian Westphal <fw@strlen.de>

gcc with W=1 and ! CONFIG_NF_NAT
net/netfilter/nf_conntrack_netlink.c:3463:32: error:
  ‘exp_nat_nla_policy’ defined but not used [-Werror=unused-const-variable=]
 3463 | static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = {
      |                                ^~~~~~~~~~~~~~~~~~
net/netfilter/nf_conntrack_netlink.c:2979:33: error:
  ‘any_addr’ defined but not used [-Werror=unused-const-variable=]
 2979 | static const union nf_inet_addr any_addr;
      |                                 ^~~~~~~~

These variables use is controlled by CONFIG_NF_NAT, so should their definitions.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

I received a bug report (no reproducer so far) where we trip over

712         rcu_read_lock();
713         ct_hook = rcu_dereference(nf_ct_hook);
714         BUG_ON(ct_hook == NULL);  // here

In nf_conntrack_destroy().

First turn this BUG_ON into a WARN.  I think it was triggered
via enable_hooks=1 flag.

When this flag is turned on, the conntrack hooks are registered
before nf_ct_hook pointer gets assigned.
This opens a short window where packets enter the conntrack machinery,
can have skb->_nfct set up and a subsequent kfree_skb might occur
before nf_ct_hook is set.

Call nf_conntrack_init_end() to set nf_ct_hook before we register the
pernet ops.

Fixes: ba3fbe663635 ("netfilter: nf_conntrack: provide modparam to always register conntrack hooks")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

This reverts "netfilter: nf_tables: skip netdev events generated on netns removal".

The problem is that when a veth device is released, the veth release
callback will also queue the peer netns device for removal.

Its possible that the peer netns is also slated for removal.  In this
case, the device memory is already released before the pre_exit hook of
the peer netns runs:

BUG: KASAN: slab-use-after-free in nf_hook_entry_head+0x1b8/0x1d0
Read of size 8 at addr ffff88812c0124f0 by task kworker/u8:1/45
Workqueue: netns cleanup_net
Call Trace:
 nf_hook_entry_head+0x1b8/0x1d0
 __nf_unregister_net_hook+0x76/0x510
 nft_netdev_unregister_hooks+0xa0/0x220
 __nft_release_hook+0x184/0x490
 nf_tables_pre_exit_net+0x12f/0x1b0
 ..

Order is:
1. First netns is released, veth_dellink() queues peer netns device
   for removal
2. peer netns is queued for removal
3. peer netns device is released, unreg event is triggered
4. unreg event is ignored because netns is going down
5. pre_exit hook calls nft_netdev_unregister_hooks but device memory
   might be free'd already.

Fixes: 68a3765c659f ("netfilter: nf_tables: skip netdev events generated on netns removal")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Pull networking fixes from Jakub Kicinski:
 "Including fixes from netfilter.

  Current release - regressions:

   - sched: act_pedit: free pedit keys on bail from offset check

  Current release - new code bugs:

   - pds_core:
      - Kconfig fixes (DEBUGFS and AUXILIARY_BUS)
      - fix mutex double unlock in error path

  Previous releases - regressions:

   - sched: cls_api: remove block_cb from driver_list before freeing

   - nf_tables: fix ct untracked match breakage

   - eth: mtk_eth_soc: drop generic vlan rx offload

   - sched: flower: fix error handler on replace

  Previous releases - always broken:

   - tcp: fix skb_copy_ubufs() vs BIG TCP

   - ipv6: fix skb hash for some RST packets

   - af_packet: don't send zero-byte data in packet_sendmsg_spkt()

   - rxrpc: timeout handling fixes after moving client call connection
     to the I/O thread

   - ixgbe: fix panic during XDP_TX with > 64 CPUs

   - igc: RMW the SRRCTL register to prevent losing timestamp config

   - dsa: mt7530: fix corrupt frames using TRGMII on 40 MHz XTAL MT7621

   - r8152:
      - fix flow control issue of RTL8156A
      - fix the poor throughput for 2.5G devices
      - move setting r8153b_rx_agg_chg_indicate() to fix coalescing
      - enable autosuspend

   - ncsi: clear Tx enable mode when handling a Config required AEN

   - octeontx2-pf: macsec: fixes for CN10KB ASIC rev

  Misc:

   - 9p: remove INET dependency"

* tag 'net-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
  net: bcmgenet: Remove phy_stop() from bcmgenet_netif_stop()
  pds_core: fix mutex double unlock in error path
  net/sched: flower: fix error handler on replace
  Revert "net/sched: flower: Fix wrong handle assignment during filter change"
  net/sched: flower: fix filter idr initialization
  net: fec: correct the counting of XDP sent frames
  bonding: add xdp_features support
  net: enetc: check the index of the SFI rather than the handle
  sfc: Add back mailing list
  virtio_net: suppress cpu stall when free_unused_bufs
  ice: block LAN in case of VF to VF offload
  net: dsa: mt7530: fix network connectivity with multiple CPU ports
  net: dsa: mt7530: fix corrupt frames using trgmii on 40 MHz XTAL MT7621
  9p: Remove INET dependency
  netfilter: nf_tables: fix ct untracked match breakage
  af_packet: Don't send zero-byte data in packet_sendmsg_spkt().
  igc: read before write to SRRCTL register
  pds_core: add AUXILIARY_BUS and NET_DEVLINK to Kconfig
  pds_core: remove CONFIG_DEBUG_FS from makefile
  ionic: catch failure from devlink_alloc
  ...

"ct untracked" no longer works properly due to erroneous NFT_BREAK.
We have to check ctinfo enum first.

Fixes: d9e789147605 ("netfilter: nf_tables: avoid retpoline overhead for some ct expression calls")
Reported-by: Rvfg <i@rvf6.com>
Link: https://marc.info/?l=netfilter&m=168294996212038&w=2
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Toggle deleted anonymous sets as inactive in the next generation, so
users cannot perform any update on it. Clear the generation bitmask
in case the transaction is aborted.

The following KASAN splat shows a set element deletion for a bound
anonymous set that has been already removed in the same transaction.

[   64.921510] ==================================================================
[   64.923123] BUG: KASAN: wild-memory-access in nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.924745] Write of size 8 at addr dead000000000122 by task test/890
[   64.927903] CPU: 3 PID: 890 Comm: test Not tainted 6.3.0+ #253
[   64.931120] Call Trace:
[   64.932699]  <TASK>
[   64.934292]  dump_stack_lvl+0x33/0x50
[   64.935908]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.937551]  kasan_report+0xda/0x120
[   64.939186]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.940814]  nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.942452]  ? __kasan_slab_alloc+0x2d/0x60
[   64.944070]  ? nf_tables_setelem_notify+0x190/0x190 [nf_tables]
[   64.945710]  ? kasan_set_track+0x21/0x30
[   64.947323]  nfnetlink_rcv_batch+0x709/0xd90 [nfnetlink]
[   64.948898]  ? nfnetlink_rcv_msg+0x480/0x480 [nfnetlink]

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

If user does not specify hook number and priority, then assume this is
a chain/flowtable update. Therefore, report ENOENT which provides a
better hint than EINVAL. Set on extended netlink error report to refer
to the chain name.

Fixes: 5b6743fb2c2a ("netfilter: nf_tables: skip flowtable hooknum and priority on device updates")
Fixes: 5efe72698a97 ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.4-rc1.

  Once again, a busy development cycle, with lots of changes happening
  in the driver core in the quest to be able to move "struct bus" and
  "struct class" into read-only memory, a task now complete with these
  changes.

  This will make the future rust interactions with the driver core more
  "provably correct" as well as providing more obvious lifetime rules
  for all busses and classes in the kernel.

  The changes required for this did touch many individual classes and
  busses as many callbacks were changed to take const * parameters
  instead. All of these changes have been submitted to the various
  subsystem maintainers, giving them plenty of time to review, and most
  of them actually did so.

  Other than those changes, included in here are a small set of other
  things:

   - kobject logging improvements

   - cacheinfo improvements and updates

   - obligatory fw_devlink updates and fixes

   - documentation updates

   - device property cleanups and const * changes

   - firwmare loader dependency fixes.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
  device property: make device_property functions take const device *
  driver core: update comments in device_rename()
  driver core: Don't require dynamic_debug for initcall_debug probe timing
  firmware_loader: rework crypto dependencies
  firmware_loader: Strip off \n from customized path
  zram: fix up permission for the hot_add sysfs file
  cacheinfo: Add use_arch[|_cache]_info field/function
  arch_topology: Remove early cacheinfo error message if -ENOENT
  cacheinfo: Check cache properties are present in DT
  cacheinfo: Check sib_leaf in cache_leaves_are_shared()
  cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
  cacheinfo: Add arm64 early level initializer implementation
  cacheinfo: Add arch specific early level initializer
  tty: make tty_class a static const structure
  driver core: class: remove struct class_interface * from callbacks
  driver core: class: mark the struct class in struct class_interface constant
  driver core: class: make class_register() take a const *
  driver core: class: mark class_release() as taking a const *
  driver core: remove incorrect comment for device_create*
  MIPS: vpe-cmp: remove module owner pointer from struct class usage.
  ...